


HP, Cthulhu and You

by ATokenATrifle



Category: Benedict Cumberbatch - Fandom, Cthulhu - Fandom, HP Lovecraft - Fandom, Martin Freeman - Fandom, Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: AGAIN!! - Freeform, Angst, Body Modification, Bottom John, Confused John, Confused Sherlock, First Time, HP Lovecraft, Hand Jobs, Johnlock - Freeform, M/M, Multi, Mutual Pining, Other, Secrets, Sherlock Has Tentacles, Tentacles, TooManyChoices has thrown Sherlock in the Thames...., Top Sherlock, Topping from the Bottom, WetLock, cthulhu - Freeform, eventual John!lock, johnticles, tentaclelock
Language: English
Status: In-Progress
Published: 2015-01-09
Updated: 2015-02-08
Packaged: 2018-03-06 18:54:50
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 6
Words: 8,938
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3144899
Author URL: https://archiveofourown.org/users/ATokenATrifle/pseuds/ATokenATrifle
Summary: <blockquote class="userstuff">
              <p>When John hears glass shatter in the middle of the night, he investigates only to find Sherlock has been hiding something from him the whole time. Something very big.</p>
            </blockquote>





	1. Shattered Glass

The sharp sound of shattering glass pierces the night-time silence. The street outside is quiet, save for the few cars and buses passing through the night. John's kept awake, not by the street light shimmering through the window, but by thoughts and nightmares. The nightmares are less frequent since moving into Baker St, but still they come. The occasional clank of dishes downstairs lets him know Sherlock is still awake and experimenting in the kitchen.

Concerned, he slips out of bed. The floorboards are cold under his feet, toes wriggling momentarily before he shuffles down the hallway. The fluorescent glow of the kitchen light illuminates the hallway with a faint yellowish tinge, and his fingers trail across the wallpaper as he takes slow steps toward the kitchen. His attention is captured by a sharp intake of breath.

Sherlock hisses in pain. He’s nicked his finger with a scalpel. Without a moment's thought he shakes his hand as if that would do something to abate the pain. No such luck. Bringing the offending finger back to his mouth he notes the amount of blood, the pooling, and that some appears to have dripped. He looks quickly to his skull, resting like a sentinel on the mantelpiece, a scarlet drop resting on the frontal lobe; his thought snapped back into the present by the creaking of floorboards.

“John?”

“Sherlock.” He answers.

“Don’t come into the lounge, John.”

“Just getting a glass of water.”

Sherlock races to pull the connecting doors between the kitchen and lounge area closed. John frowns, but thinks nothing more of the curious behaviors of his flatmate. His eyes are barely open under the glaring kitchen lights; he shuffles around for a glass of water and switches on the tap as he watches Sherlock move around on the other side of the frosted glass.

“I’m serious, John. Please don’t come in here.” Pain is searing through Sherlock’s spine, the ache of skin splitting all too familiar.

“It’s okay, Sherlock. I’m sure it’s a big secret. It’s fine.”

John returns to his room and sits on the edge of the bed. Sherlock, still in the lounge, is overwhelmed by pain. Slowly he slips down on the couch; this feeling is familiar enough to know what’s coming. Hastily, he unbuckles his pants and they drop around his ankles. Pain tears through his legs, teeth gritted against a scream as a first, a second, and then a third, fourth, fifth and sixth cut appear. Three either side of his spine at his tailbone. The gashes are clean with little to no blood.

Sherlock clamps down on the cry threatening to escape, trying to stay silent throughout the pain. This is the first episode he’s had with another person in the house, and he doesn’t want to be discovered, at least not this soon and certainly not this way.

Reflexively, a foot lashes out, knocking the coffee table. Instability brings the teapot and cup crashing onto the ground. Sherlock can hear John moving around upstairs, alerted by the sound. It wasn’t something that would normally occur in the still of night.

For the second time that night, John starts his walk down the hallway. The closer he gets, the more he can hear.

“Sherlock? Are you okay?” He can hear writhing in the lounge room.

“Fine John. Just fine. Go to bed.”

“You don’t sound fine.”

“John. Go. Now.”

A dull thud hits the floor, followed by another, another, and another. John loses count of how many there were, but keeps walking toward the door at the end of the hall.

“John. Go.” Sherlock’s voice, wracked with pain.

It was too late. The door slides open with a slight creak. John’s eyes widened at what he sees before him.

Sherlock Holmes, the world’s only consulting octopus.


	2. The Curse

**Summary for the Chapter:**

> Now that Sherlock's secret is out, what will John do? 
> 
> A late night confession and discussion that will bring them closer to solving the mystery and, to each other.

John stood momentarily, unsure of where to rest his eyes. Sherlock was horrified, embarrassed, scared. John’s response, still unspoken, but very much written in his eyes; he was terrified as well, but never one to flee a battle, John stood his ground.

“John -.”

“Sherlock.”He tried not to look deliberately at the tentacles. “What is this?”

“I didn’t want you to find out like this.”

“Not sure there'd be a good way to find out.”

Sherlock’s eyes glinted with tears. “Better than this, though.”

John stood, his eyes still averted.

“Please look at me, John.”Sherlock was _almost_ begging.

A thousand thoughts flashed through John’s mind at once, and none of them made any sense whatsoever. Human octopi hybrids don’t exist. They can’t exist. It’s _impossible._ As if to read his mind, Sherlock spoke. Quiet, embarrassed, timid.

“Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.”

John turned to face him. “No Sherlock, this actually _is_ impossible.”His hands changed constantly, balled up one minute, fingers outstretched the next. “This is …”

“John. It is improbable, but not impossible.”Sherlock reinforced.

“Of all the things, Sherlock, all the things. I’ve got a right mind to just leave. I thought we were close and you couldn’t tell me this?”

“Please don’t leave, John.”Hell, he _was_ begging now.

John rubbed his forehead. “How did I not know this?”

“If you’ll give me some time, I will explain it.”

“I sense this might take a while.”John walked slowly and carefully over to his chair.

Sherlock stood slowly and moved over to his chair. Wracked with nerves, he took the skull from the mantelpiece as he sat.

“John, meet HP.”

John screwed his face up. “As in the sauce?”

“As in Lovecraft.”Sherlock was deadpan.

“Right, so what does Cthul-.”John stopped, realising what was coming from his mouth. “Never mind. Continue.”

A cursed skull. A joke in primary school, a black haired boy, a few lowly muttered words and Sherlock had been struck with the Curse of the Cthulhu Skull. Should a drop of blood touch the skull, Sherlock is transformed into an octopus. The only way such a curse is broken, or so he'd been told, is to find one's soul mate.

“Soul mate?”John looked at him. “As in a woman.”

“Well. It could be a woman, or a man, John. I don’t know.”

“Right. And what happens when this…soul mate...is found?”

“The curse is broken, of course.”He gave a non committal wave.

“Do you know who your soul mate is?”

“Clearly not.” Sherlock nodded down toward the tentacles.

“So this only happens when you get blood on the skull?”

“Correct.”

“Okay, so it should be fairly easy to avoid getting blood on the skull.”

“In theory, yes.”Sherlock agreed. “This is the first time this has happened in months.”

The two men relaxed again. John still struggled to make sense of the situation, but writing it off to an ‘occasional’inconvenience made it much easier to deal with. Sherlock could read his face, and seeing him tension falling from his shoulders was helping him relax in his present, compromised situation.

"So, you don't usually have tentacles, where do they go between.....episodes?"

"I go out, have a bit of a dip in the Thames, come home, go to sleep and they're usually gone in the morning."

"Right then, I suppose you'll be heading out."

"I'll grab my coat."

"Sherlock," John said hesitantly, "Before you go, can I..you know...have a look?"

Sherlock seemed relieved that John was overcoming his initial revulsion and moved closer, to stand in front of John, tentacles clustered around his waist, waving gently as if sniffing the air.

“"Sherlock....What are they doing?" John asked as the tip of one damp tentacle pressed inquisitively at the elastic at the waist of John's pyjama bottoms.

Sherlock looked down at the offending limb, "I don't know....I'm not doing it. Don't move, I think it's just...exploring."

Another, thinner extremity joined the first, curling around the string tie at the front, seemingly fascinated by its ability to grasp and tug. Meanwhile the first trailed along the top edge of the elastic, rolling gently between the soft cotton material and the warm smoothness of John's exposed abdomen testing the different surfaces.

"It tickles," John squirmed slightly, "Do you think it knows?"

Sherlock shook his head in wonder, watching the two limbs work independently of his conscious control, "They do seem to be enjoying themselves."

John giggled again as he watched tiny suckers attach and detach from his skin with a soft 'pop'. It seemed obscenely loud in the quiet room and looking up at Sherlock he laughed again at the aghast look of embarrassment on his face.

"Hey, Sherlock, it's OK. It's not as if they're going to hurt me." His tone became serious for a moment, "They're not going to hurt me, are they?"

"Oh, I shouldn't think so, they seem to like you. It's fascinating actually, I've never seen them do this with anyone before."

The two of them sat together in front of the fireplace for some time as Sherlock's tentacles roamed around John's torso, pushing up his T-shirt in increasingly bold forays into unknown territory. Like bemused but proud parents, they both watched in silent companionship as the limbs mapped John's skin, lingering in grooves and curling proprietorially around curves of muscles.

John hissed a breath.

Sherlock looked up in alarm, "What? Are you OK?"

"No...yes...I'm....Oh...It's ummm...found a ...." John wriggled in discomfort, "..a nipple... Oh..that's ..weird."

Sherlock pushed up John's T-Shirt to find one of his tentacles attached with a band of suckers up John's chest and the narrow tip delicately flicking the now raised nub of John's nipple.

"I'm sorry, I'll just.." Sherlock reached out intending to remove the offending limb until one of his own tentacles shot up to encircle his wrist, effectively holding his hand away from its destination.

Looking down at his hand, to John's chest where the tentacle tip was still enthusiastically discovering John's reactions, and then up to meet John's eyes, Sherlock cleared his throat awkwardly, "Apparently they don't want to be interrupted. God, I'm sorry, John."

"Ummm...OK..." John blushed, "It's...look it's OK....it's just a bit.....Christ..." The tentacle's lubricating ooze had been building up in the area for some time and it now began smoothing it around and across John's nipple, attaching and detaching tiny suckers across the surface.

As if to make matters worse, the lower tentacle, that had seemed content to wind in an out around John's waist chose that moment to breach the elastic waistband and make a determined advance in a generally southward direction.

"Sherlock!" John stuttered, suddenly sure as to the slippery appendage's likely destination.

Sherlock looked up, their eyes holding a similar, horrified disbelief as Sherlock's remaining wrist was disabled by yet another limb.

"I....John...I don't know what to do. I'm not doing this, I don't understand what's got into them." Sherlock's voice was verging on panic, "They've never done anything like this before.

John's breath caught, the lower limb clearly having reached its destination and he looked stricken, "Well it looks like this is happening regardless of our views on the matter."

Sherlock glanced at the tentacles, his wrists pinned by two, another two roaming John and the rest twitching and shivering gently on the floor in what was obvious excitement. He looked at John and asked quietly, "What can I do? How can I help?"

John's eyes flickered shut as he balled his fists on his thighs, "It's OK, Sherlock...It's..." He pulled in a rough breath, "God...I'd be lying if I said it was unpleasant..it's....fuck...it's just.....Oh God" John's voice trailed off as he shifted where he sat, his hips giving a slight reflexive thrust against whatever was happening within the cotton confines.

Sherlock's eyes wandered to John's crotch where he could now see the outline of his own tentacle, clearly stroking steadily against John. He didn't need deduction to know what it was doing. He felt his own pulse rate increase as his face heated. "I'm sorry."

"No..." John managed, "S'good...S'very good." John locked eyes with Sherlock, surrendering to the situation, "Can you feel what it's doing?"

Sherlock blinked a moment, focussing inward, connecting with the sensations from his new appendages. It would be easy to lie, but with John so vulnerable and at Sherlock's mercy, he deserved the truth. Sherlock swallowed as his eyes dilated and whispered, "Everything...I can feel everything, John."

"Can you......" John made another abortive rocking motion, his eyes searching Sherlock's.

"Anything." Sherlock whispered.

"Can you..come here. I think it'll feel less weird if I can touch you. Can I..." at the words, another of Sherlock's tentacles lifted from the floor and circled around John, clearly pleased at the suggestion, "Can I touch you...please?"

Following the limb's suggestion, Sherlock shuffled forward, the two tentacles around his wrists, having decided their point had been made, retracted leaving Sherlock free to cup John's face on his hands and press a gentle kiss to John's lips.

"Whatever you need, John. Take it."

Hesitantly, John smoothed a hand down Sherlock's dressing gown, over the sharp jut of his hip and toward the front. Sparing a last look into Sherlock's eyes and receiving a calm nod of acceptance, he brushed his fingers lightly across the fabric at the crotch, somewhat heartened to find Sherlock clearly aroused beneath the thin material.

"It's OK, John," he whispered roughly, "I want you to...I think they knew it before I did."

John palmed the fabric more firmly and gasped as the tentacle wrapped around his own cock responded in kind with an enthusiastic stroke. Another tentacle eased from the floor at Sherlock's side and insinuated itself down Johns pants, and John felt it work it's way down to cup his balls gently, massaging softly.

John pressed his tongue against Sherlock's mouth, seeking and being granted entrance as he leaned closer and slid his hand up the fabric of Sherlock's crotch, then reversing direction at the waistband, pushing aside the soft cotton and plunging down to wrap his fingers around Sherlock's length.

Sherlock groaned against John's mouth, his hot breath around their intertwined tongues as he slid his hands around John's neck.

John tried valiantly to keep hold of some semblance of control. So many points of contact; Sherlock hands on his neck and face, another limb continuing its assault on his nipples, yet another wrapped firmly around his waist, making lazy circles at the small of his back and finally, the two at his genitals. One stroking and fondling, the other delicately exploring his balls and pressing against his perineum. It was just too much to handle and still try to focus on getting Sherlock off.

But Sherlock missed nothing. Somehow sensing John's silent struggle, he moved one of his hands down to cover John's, helping with the sporadic yet confident rhythm. In another situation, it might be seen as a harsh judgement of John's technique, but here, with the combined onslaught of Sherlock's appendages, John simply mumbled a broken Thank You and they grinned against each other's mouth at the insanity of the situation and continued to thrust against each other.

"Christ...yes, Sherlock....like that...just keep..." John gasped against his mouth after what seemed like hours basking in the overwhelming attention.

A muffle grunt was all Sherlock could manage, clearly having his own struggles with the sensory input from his limbs. "John..."

"I'm....yes...Oh!" John's hips stuttered once, twice and thrust forward and Sherlock groaned as he tried to process the feelings of John's orgasm as relayed by his new appendages. He gasped and wetness puddled over their linked fingers.

Heads cradled in the crook of each other's necks they gasped for breath as the lingering shudders abated and they crawled closer to collapse in a haphazard pile in front of the fire.

John was the first to break into soft, slightly hysterical giggles, "That was....weird...I'm calling it, weird but great."

Sherlock looked at him from under drooping eyelids, "You OK with weird but great?"

John giggled again, "Don't know.....might have to try it again to be sure."


	3. Swimming in the dark

**Summary for the Chapter:**

> So, to get rid of Sherlock's tentacles he just needs a swim and a nap. Let's see how that goes.

“So you just…..go for a swim.”

They stood, side by side in the shadows under a bridge along a deserted stretch of the Thames. The cab ride had been silent and somewhat awkward, with both of them coming to grips with the sudden, if not unwelcome change in their personal relationship, and lost in their own thoughts.

@@@

**Earlier**

Once they’d caught their breath, the reality of what they’d just done together began to sink in and after silently wiping his hands on his own jeans, John quietly got up and padded to the shower, leaving Sherlock sitting alone on the floor.

Unwilling to disturb John in the bathroom, Sherlock had instead wandered to the kitchen and methodically cleaned his now docile tentacles one by one. He was still mystified by the appendages actions and their rather extreme reaction to John. In the dozen or so transformations he’d undergone in the past, they’d shown no inclination to touch another human being, let alone the intimate interaction they’d clearly been intent on imposing on his Doctor.

Fortunately, Sherlock thought, no harm had been done. The situation, given John’s previous stated sexual standing, could have been a disaster and, although the thought of applying the word made Sherlock sick, the word 'force' wouldn't be misplaced. Sherlock knew that John was in all likelihood closer to bisexual than straight, but knowing it and John acknowledging it were two very different things.

Best to just pretend it didn’t happen, Sherlock thought. Yes, allow them both to write off the episode as some sort of tentacle-driven aberration and get on with The Work. Let the matter drift into the distance and never mention it again. However good it had felt, however seductive the feeling of John’s hands on his body might be, John wouldn’t have sought this if the peculiar situation hadn’t forced the issue. Sherlock nodded, his mouth tight…Yes…that was best, never mention it again.

@@@

Meanwhile, John stood slumped against the tiles picturing the last hour as it replayed on an endless loop in his head.

He’d never participated in an orgy. Not that he’d have turned it down, just that he’d never been invited. If the feeling of Sherlock’s hands and…..other limbs all touching him at the same time was an indication of what the experience could have been like, then he’d seriously missed out.

Jesus, he’d never come so hard in his life, he thought.

He wondered if, in Sherlock’s panicked stream of apologies, the detective had had the presence of mind to recognise John’s enthusiastic capitulation for what it was; a heartfelt, non-verbal cry of “Oh God, at last.”

It was a pity it had taken this odd, supernatural event to push them over the barrier between flatmates to…..more. One that, after an abortive and rejected attempt at Angelo’s on that first night, John had been unwilling to press for again.

But now….now there was hope. He’d wait for Sherlock to mention it and John would finally tell him how much he’d wanted this to happen and they could begin this relationship properly.

@@@

**Back at the Thames**

“Yes, that’s pretty much it. I wade in, swim around for ten minutes or so, and then after a good night’s sleep, I’m back to normal. Sherlock began unbuttoning his shirt.

John nodded, glancing down at the tentacles that emerged from the bottom of Sherlock’s untucked shirt. They still hadn’t talked about….before, but Sherlock had a tendency to focus on whatever matter was at top-of-mind so perhaps that was the cause.

“I’ll just,” John picked up the Belstaff and shirt Sherlock had negligently discarded on the shore, “…mind your clothes then.”

Sherlock cast a glance at John in the dim light. There was something askew in their usual banter. The conversation seemed forced and with frustrated sigh, Sherlock nodded his assent, “If you would. You can use the coat to keep you warm…..if you like.” He tried for a grateful smile and feared it looked condescending instead.

“John…..” he began, not knowing exactly what he wanted to say. _Thank you for being here, with me._ That was close to what he was searching for. _I want to touch you again, even after the tentacles_. That was even closer. In the end, he settled for “I’ll be back soon.” As he shrugged off his trousers and walked barefoot toward the water’s edge.

John watched him pick his way over the stones toward the water, distant streetlight setting the pale skin aglow against the shadows and rocks. He’d never seen Sherlock naked, a fact that may surprise most of Scotland Yard. For a man with a propensity to wander the flat in various states of undress, Sherlock was fastidious about never relinquishing that final layer of covering, be it sheet, pyjama pants or towel.

Now John had the chance to watch shamelessly as Sherlock’s thighs and arse muscles flexed and clenched as they maintained his footing on the uneven surface. The long, slightly slimy appendages waved gently around him, some reaching out to the water, others seemingly extending in an offer of more balance. John firmly pushed down an almost overwhelming desire to shed his own clothes and run after the man and join him in the water and swim with him. He longed to see how Sherlock’s tentacles would thrust and drive them through the water. Instead, he carried his armful of Sherlock’s clothes to the bridge overhang and settled with his back against the chill bricks.

@@@

Sherlock couldn’t quite articulate how the feeling of being in the water when his tentacles were present was different from any other time, but it was. It was as if on some deep visceral level, he belonged in the water at times like this. The usual freezing water was instead simply a refreshing chill, and the usual exertion required to remain afloat became a calming weightlessness with an almost instinctive ability to navigate through the welcoming liquid.

He relaxed as his appendages drive him through the water effortlessly and he rolled onto his back, letting them wave below him in the dark water in gleeful abandonment. Rotating onto his chest again, he looked to where he could see the vague outline of his friend, huddled under the overpass. He wondered what it would be like to have John in the water with him, here where his tentacles could wind around his sturdy form, holding him aloft in the water as they swam in companionable synergy.

Instead, he was alone in the quiet darkness. He dipped his head under the water one last time and headed for shore. Stepping out on the bank, he saw John rise and stride toward him, a towel they’d brought with them already in hand to shield him from the night-time cold. John approached and immediately enfolded him in the fluffy cotton and for a moment, Sherlock indulged in the feeling of the almost-hug before they stepped apart.

John was smiling up at him, “You looked like you were enjoying yourself, I could see you from over there.”

Sherlock realised he was grinning and he tried to find the words that would convey the experience clearly, “It’s an unusual feeling. As though I belong there, it’s like when I crack a case, that moment of brilliance when everything makes sense. It’s hard to explain.”

But John was nodding, “No…no, I understand. It’s like when I was operating in Afghanistan, everything I need was at my fingertips, just when I needed it, and I had the knowledge and skill to do the job. I could have taken on the world.”

Sherlock reached out and grabbed John by his upper arms, delighted, “Yes! That’s it exactly!” He looked at John fondly and murmured more softly, “I should have known you’d understand.”

John waited for Sherlock to say more and when it became evident that nothing was forthcoming, he blushed and looked away, breaking the intimacy of the moment, “Yes, well, let’s get you dry and back in a cab.”


	4. I LIKE them

**Summary for the Chapter:**

> The morning following Sherlock's swim..and his tentacles should be gone.

“Ummmm, Sherlock” John paused at the door of the kitchen and observed his flatmate, working at his microscope.

“Yes…I know.”

“The…ahhh..tentacles,” John paused before stating, “Not gone.”

Sherlock looked up and with a tense tone, replied, “Obviously.”

John continued with their usual morning routine, mugs from the top cupboard, bread into the toaster, “I thought they were supposed to…”

Sherlock pushed the chair back with a scrape and turned, his frustration obvious, “Well clearly they haven’t, have they? I don’t have a rule-book John, I only have previous experience. THESE,” he gestured to the appendages, and they helpfully gestured back, “should be gone. They’re ALWAYS gone.”

John leaned back against the kitchen counter and crossed his arms, balancing Sherlock’s temper with quiet consideration, “Well, looks like you’re stuck with them for another day. To be honest, I’ve sort of gotten used to them. I think I might miss them when they’re gone.”

Sherlock sniffed derisively and muttered something unintelligible. One of the limbs was amusing itself by untying and retying Sherlock’s dressing-gown belt and he glanced down at it in bewilderment.

John pursed his lips, trying not to laugh as another wound its way up to hold the fabric still while the first worked on tying a neat bow before pulling it apart again. Sherlock met John’s eyes with a look not unlike despair.

“It would be different if I had more than rudimentary control over them, but it’s like patting your head and rubbing your stomach multiplied by three. The moment I try to concentrate on anything else, I find they’ve decided to take my shoes off, or push books off the desk or wipe themselves on my hair leaving whatever the hell that stuff is…everywhere.” He poked a finger at a dark curl and it came away wet with sticky goo.

John stepped closer and lay a gentle hand on the one trying to untie the belt again, stilling its movement and watching as it instead turned to inquisitively poked and slid across John’s wrist. “They’re probably just bored, Sherlock. They are a part of you, after all.”

“I don’t care, John. Tie them up, amuse them, do whatever you like with them, just…..something. They’re driving me insane.”

Oddly enough, it seemed that perhaps the tentacles detected something of Sherlock’s anger because as John looked down, a second, third, and fourth gravitated toward John, burrowing into nooks and crannies in his jumper and collar as if to hide from their frustrated owner. They nestled against John, warm and alive, seemingly content to simply rest closer to him, confident in his ability to keep them safe from their manic owner.

Watching this transition take place, Sherlock’s ranting died away and he looked at the living ropes of flesh now joining the two of them together. They’d flushed to a healthy pink and vibrated softly in something that could be described as a purr. He threw his hands in the air in defeat but didn’t pull away.

John looked down, “I like them. Sorry. I know they bother you and get in your way but…look at them, Sherlock. They’re part of you and….I LIKE them.”

Sherlock smiled for the first time that morning, listening to the almost soundless purr, “Well…it’s safe to say they like you too.”

Two more tentacles edged up toward John, apparently more hesitant that the earlier ones and Sherlock rolled his eyes, speaking to them as if to a small child, “Yes…go on then” and watched as they too curled up against John and flushed the same happy pink.

John laughed softly as the tentacles clustered around him, seeking gaps in his clothing and rubbing wetly wherever they found skin.

“Doesn’t the….”Sherlock winced at the word that came to mind, “…lubrication bother you?”

John glanced up at the word and grinned, “Well, you know what they say.”

Sherlock shook his head.

“You can never have too much lube.” John chuckled and then laughed louder at Sherlock’s blush.

One of the thinner appendages detached itself and slapped gently at John’s face, leaving a sticky mark before descending back to his collar and John looked up suddenly. “Was that it, or you?”

Sherlock’s eyes narrowed before a broad grin broke across his face, “It may not have been entirely involuntary. Sometimes our goals fortuitously align.”

John decided that was the best opportunity he was going to get to raise the topic, so he took it, “So….I have to ask….yesterday? How much of that was you?”

Sherlock fidgeted as much as he could, tethered to John and avoided his eyes, “I…well..”

Sherlock might be the detective, but John saw the way this was going and stepped in before Sherlock could sabotage the situation, “Because, Sherlock…I just want to say..” John cleared his throat and gave a gentle squeeze to one of the tentacles nestled at his waist, “It was the best idea you’ve ever had.”

John felt the shudder that rippled through the tentacles and watched as the pink flushed to a dusky red, the suckers plumping noticeably along their lengths, “Well….that provoked a reaction,” he murmured huskily.

Sherlock shuffled forward a little and his hands came up, finally, John thought, to rest on his hips in a gap between two of the broader limbs. He tugged John toward him gently, until they were not quite touching, “So…You didn’t mind…” Sherlock glanced down.

“Mind? I’ve been trying to work out how to get them to do it again.” John ran a hand along one of the exposed tentacles, now visibly wet with liquid and added quietly, “I know you’re sorry they’re still here this morning but….I have to be honest…I’m REALLY not.”

Sherlock brought their bodies gently together, his arms slipping around John’s back, “So you don’t think they’re…..” he trailed off.

“Unique…bloody amazing….like you? Yeah, they’re all that. What have you always said, normal is boring? These things…” John gave one a firm stroke and Sherlock’s legs nearly went from under him, “…..NOT boring.”

“You….John Watson are….” Sherlock dragged in a shaky breath.

“Brilliant…amazing….fascinating?” John began peppering kisses up Sherlock’s neck and over his ear.

“Mine,” groaned Sherlock burying his head in John’s shoulder and sucking on the skin there.

“Jesus, Sherlock…..sofa.” John managed.

Sherlock shook his head against John’s collar bone where he was enthusiastically working a mark onto the skin. He pulled off and muttered, “Bed” before starting to push John in the direction of the hall.

Sherlock’s tentacles were deftly making short work of buttons and zippers and by the time Sherlock had directed John through his bedroom door, John’s jeans and underwear were threatening to trip him where they bunched at his knees. He kicked them off together with his shoes and pushed the door closed behind them.

Their shirts and Sherlock's robe were discarded shortly afterward and they found themselves helplessly giggling against each other’s mouths as two of Sherlock’s tentacles pushed down his pyjama pants with what could only be described as irritated haste, leaving them bare and pressed against each other.

“You know, Sherlock…” John mumbled against Sherlock’s lips, “I think I’m getting the better end of this deal.”

Sherlock’s appendages seemed to be everywhere, touching, stroking, pressing. Meanwhile, Sherlock’s hands were buried in John’s short grey-blonde hair as he held the shorter man still and silenced his comment by crushing their mouths together again.

He pulled back, “Wrong, as usual….feeling…everything.” He dove in again, twining their tongues together.

One tentacle had wrapped itself around both their cocks and was moving lazily, the ever-present viscous fluid making the strokes smooth and languid. John felt the warm, wet touch of one behind him and with a stuttering gasp, flinched as he felt two more gently easing his arse cheeks apart.

Sherlock stilled for a moment and John was surprised to feel that for once, all of his tentacles paused too. Their faces inches apart, Sherlock met his eyes and asked in a whisper, “OK?”

 _Ah, so this isn’t all the tentacles idea…that’s…excellent_. John thought and then nodded, easing into Sherlock’s arms and another long kiss.

The stroking resumed, as did the tentative touch at his arse. The two were joined by a third, impossibly wet and slippery, and it eased its way between his spread cheeks as John groaned at the sensation.

“Everything..” Sherlock muttered seemingly in wonderment.

The tip flicked against John’s hole, as gentle as a tongue, softer than a finger, it pressed and probed until John was pushing back against it, wordlessly inviting it further.

As it breached first the outside ring and then eased in further, both their legs wobbled dangerously and Sherlock managed to tip them onto the bed behind them, leaving John splayed across his hips, their chests pressed together.

In the back of his mind, it seemed very odd to have Sherlock’s hands cradling his cheeks, and yet, he could still feel their cocks being stroked and of course the feeling of being gently worked open, the appendage flexing and thickening repeatedly before easing further inside.

John’s fingers threaded through Sherlock’s curls, anchoring them together and he delighted at the hiss and arch of pleasure as he tugged gently this way and that.

“C’mon Sherlock, stay with me…” John tucked his head down and bit gently on Sherlock’s earlobe as it became clear that the detectives concentration was drifting, buffeted from so many sources of input. The pale eyes opened and focussed on John’s and he smiled up at him.

“Still….here….” he panted, “Sorry….all a bit….much.” He groaned again as a second tentacle slid in next to the first inside John’s pressing heat and curled, searching.

John arched as the suckers brushed against his prostate, “Oh….again,” and gasped as the movement was repeated.

Sherlock looked up at him, awash with pleasure, eyes hooded and glazed. He placed his hands, blessedly free of other tasks, on John’s shoulders, providing support as John rocked against him.

Without warning, the tentacles at John’s arse thinned and retreated and John whined at their sudden absence. They curled around the tops of his thighs insistently urging him up Sherlock’s body as the one clasping their cocks together released its hold and moved away.

Their meaning was clear and John went willingly. Sherlock’s eyes widened before rolling back in his head as John manoeuvred, aligned himself against Sherlock, and pushed down.

Sherlock’s breath stuttered and his hands fisted desperately, eyes flying open as he sought out John’s face to help ground himself and stave off the inevitable. Tentacles twitched and grasped and John held motionless giving Sherlock much needed time to gather himself.

Releasing a shaky breath, Sherlock nodded wordlessly and tilted his hips up encouragingly, giving permission for John to grind down against him.

John lifted slightly and settled again and after an approving moan, took charge and repeated the action.

"Harder." Sherlock's vision had cleared a little and John obliged, with more force this time and Sherlock canted his hips up to meet him as he dropped back down with a grunt.

"Fuck, John..Harder." Taking the hint, John leaned forward, his hands on Sherlock's shoulders to give himself better leverage and slammed down in earnest, swearing as the move pushed Sherlock's cock against his prostate and light burst behind his eyes.

"Again." Sherlock growled, rough and low and John threw what little restraint away as he set a brutal pace, slamming them together over and over again, as their mouths fell open to gasp each breath.

Sherlock's hands came to rest on John's hips, gripping hard enough, John thought, to leave bruises as he urged both speed and force and supporting John's increasingly erratic rhythm and balance. John took his cock in hand and stroked roughly, the remaining ooze from the tentacle making his grip swift and easy.

"John...christ...more..." Sherlock begged brokenly as John rode him, his thigh muscles burning and sweat dripping down his face. "Close...so close..."

Sherlock shifted slightly, pushing his feet more firmly under his bent knees and the change in angle was all they needed. Sherlock cried out, his arse lifting off the bed with the force of his orgasm, his stomach clenching tight even as John's cum streaked across the skin with his own orgasm.

John fell forward heedless of the mess between them to pant for breath against Sherlock's chest, pinpricks of light still flickering behind his closed eyelids.

"Fucking brilliant..." John muttered...."Amazing....brilliant....perfect."

"Mmmmm," was all Sherlock managed.

As they settled, their breathing resuming a more normal pace, John took a moment to ease off Sherlock and roll next to him. Something was different and it took him a moment to realise what it was.

"Sherlock....?"

"Hmmm?"

"Your tentacles have gone."


	5. It takes two to tango

**Summary for the Chapter:**

> Now that Sherlock's tentacles are gone, what's next. Will John be happy to see them gone forever?

John looked at him, and back to where the tentacles had previously been, running a single finger along the light marks they left against his skin. Eight singular lines, very faint, but noticeable if you looked hard enough. 

“We can just bring them back, can’t we? A drop of blood,” John suggested. 

“Perhaps yes.” Sherlock yawned. “But, do we want to though?”

@@@

A morning spent rifling through paperwork, case files, and unpaid bills, the unspoken question lingered without a chance to be aired. After lunch, while typing at his blog, John stopped for a moment, the thought having circled his mind for most of the day. 

“Sherlock.”

“Hmmm.”

“So, these tentacles.”

“Yes, John.”

“They come out with blood, correct? On the skull.”

“Yes.”

“Is it just your blood that works on it?”

“Well, I don’t know John! It’s not like I’ve had a world of opportunity to experiment! I don’t see people lining up waiting to donate blood.” 

“Alright. God, I’m just asking.” 

It took another 24 hours before John broached the subject of ... experimenting.

“How do you mean?” Sherlock looked at him. 

John placed the skull on the kitchen bench and looked at him. “You don’t know why it happens, or if you’re the only one. So test me.”

“Test you?” Sherlock scoffed. “You’re actually serious?”

“Of course I am.” He scavenged around to find a pin. “You go first.” 

“Me? Why me? We’re experimenting on you.” 

“Well, because I happen to like the tentacles, so even if only you end up with them, it’s a win/win isn’t it?”

“Lunch." Sherlock said suddenly.

“What?”

“You need to eat. If we're doing this, and I'm not saying we are, trust me, you'll want a full stomach.” Sherlock dismissed with a wave of his hand, sliding his coat on. “Come on, downstairs, we’ll go to Speedy’s.”

@@@ 

“We can’t be certain that this will work on anyone other than me, John.”

“True. That's why we’re experimenting.” John hissed, shovelling hot chips in his mouth. 

“And if it does work, we don’t know if they’ll go away again. Do you want to be stuck like that?”

“I could just... borrow your coat. You have a few of them.”

“True enough.” Sherlock agreed. “What I’m saying is, we don’t know.”

“Of course we don’t know, that’s why we experiment. Hypothesise, come up with solutions.” 

“This isn't because this is a thing now...” 

“That what is a thing?” John wiped his mouth with a napkin. 

“This... thing... you and me.” Sherlock gestured between them with a wave of his hand.

“For God’s sake Sherlock.” John threw his head back in defeat. “Yes, yes we’re a ‘thing’ if that’s how you want to term it. But you’re a man of science, yeah? So, come up with our hypothesis, and then experiment based on that.”

“You’re all for this... experimenting, aren’t you John?” A crooked smile formed on Sherlock’s lips, catching John off guard. 

“Yes, well. The last few days may have...expanded my horizons?” 

@@@

Back in the kitchen, the door to 221B locked and Mrs. Hudson out for the afternoon, Sherlock looked at John, then at the skull again. Knowing the consequences of being fully clothed during a transition, both men were dressed only in their bath robes. 

“What’s your theory, your null-hypothesis?” Sherlock looked at him. 

"My what?"

"Null hypothesis...it's the scientific term for....." Sherlock rolled his eyes, "Don't bother, I'd forgotten for a moment that this was something other than you indulging in a tentacle-based sexual fantasy."

John grinned, “My theory is you’re not the only one it works on.” 

“I’ll go first, shall I?” 

John leaned forward and pricked Sherlock’s finger. What started as a tiny speck soon grew to a large drop. 

“Bugger it, let’s do this together.” John pricked his finger and forced blood through the skin. 

“Wait, John, are you sure?”

“Of course I’m sure. If it doesn’t work, it doesn’t work. If it does work, well, it looks like we’re going to the Thames tonight for a bit of R&R.” 

Both men pressed their fingers on the skull, the familiar pain coursing through Sherlock immediately. John watched on helplessly as he moved to the lounge where there was more room for a transition. He hated the sight of Sherlock in pain, but he could do nothing to help as we writhed, teeth gritted, and tried to ride out the pain. 

“It’ll be over shortly,” Sherlock hissed. “It’s okay.” 

Knelt in front of Sherlock on the couch, John watched as tentacle after tentacle appeared from the markings in Sherlock’s skin. His transition almost complete when pain shot through John’s spine, blinding light flashed behind his eyes and sent him stumbling back onto the ground before his vision narrowed and the world went dark. 

It was late afternoon when John awoke on the lounge floor, Sherlock sitting up next to him, a smile of contentment on his face. Confusion clouded his mind and it took him a moment to fully regain consciousness, doing his best to sit up, but feeling very heavy in the general trouser area. 

Two sets of tentacles were sprawled out across the floor. Two were entwined as if holding hands, two more were tickling each other, which John could feel with alarming sensitivity. More still were seemingly doing whatever they wanted, two moving their way across John’s body, as if to get a feel for their host, and two reaching out to smooth their way over Sherlock’s face and through his hair. 

Sherlock watched on as John took the situation in, a look of shock, awe, surprise, and a tiny bit of horror smeared across his face as he tried to make sense of what had happened. John looked down into his lap and around him, before looking back at Sherlock again. 

“Well, I guess we’d call these Johnticles, would we?” Sherlock smiled knowingly.


	6. John's aggressive Johnticles

**Summary for the Chapter:**

> WARNING: Dubious consent (although not really, because our boys always want each other)
> 
> Virtually no plot...just port..tentacle porn..LOADS of tentacle porn.

"OK, this is weird." John's staring at the thickest of the tentacles and his eyes widen as it sluggishly lifts from the floor, "Bloody hell, Sherlock...I'm doing that, I'm making it lift from the floor."

There's a low chuckle from beside him, "You might like to keep an eye on the others."

John looks up to find one wrapped around the teapot on the side table. It's determinedly dragging it to the edge and only John's quick thinking stops it from crashing to the floor. The flurry of activity sets his tentacles writhing around himself with excitement.

"Take it slow John, You've tripled your limbs, it takes a bit of getting used to." Sherlock lifts himself to his feet, smiling as a couple of his tentacles reach backward toward John. "I'll get us some fresh tea."

"Can you..." John looks around himself at the mass of shifting pink appendages, "Give me a hand up? Every time I try to push off, one of these things swipes my hand out from under me."

Sherlock leaned down to offer a hand and it was grasped by not just John's strong fingers but two tentacles that wrapped tightly around his wrist.

"Seems like yours like me as much as mine like you." Sherlock noted the way one of John's was tapping out a pulse-like rhythm on the inside of his wrist.

John looked down at them, something uncomfortable crossing his face, "Umm, Sherlock. I can't get it to let go."

Sherlock shrugged it off, "Well, I told you mine seem to have minds of their own. Try concentrating."

"I am.." John's brow creased, "Believe me, I am. It's as if...I know they can hear me, but they're actively ignoring what I'm saying."

Sherlock tried a little tug against the restraining tentacle and hissed is it tightened.

"No..." John shook his head urgently, "No, don't do that. I got a pretty clear indication that they don't like you pulling away."

"What sort of indication?" Sherlock looked dubiously at John's tentacles twitching against John's sides.

"It's hard to explain, sort of.....a rush of anger. You know, like when someone barges in front of you in line."

Sherlock's mouth turned down as he considered. One of his own tentacles lifted up to tentatively prod at the constricting binds around his wrist and they both gasped as another of John's appendages whipped up to slap it away. They exchanged worried glances.

"Yours certainly seem.....crankier..than mine. Maybe we should just...sit back down." Sherlock nodded toward the floor in front of the fireplace.

John nodded worriedly and they began a synchronised shuffle, settling on the rug with their combined limbs arranged about them.

"What do we do now?" John asked as Sherlock's tentacles reached out to gently touch John with familiar inquisitiveness.

"Now...."Sherlock looked down at where his fingers had started to go numb in the unforgiving grip of John's, "....I suppose we wait."

@@@

"John?" Sherlock is just on the edge of sleep when he feels the slick wetness slither against the exposed flesh of his stomach. There's no reply and as he turns to his partner laying beside him, he sees John's face relaxed and mouth open.

"John!!" He says more loudly as the tentacle roughly pushes aside his boxers and wraps firmly around him, the tip edging between his foreskin and head, beginning to tease him into responsiveness. John lays slack and unresponsive and Sherlock suspects there may be more at work than simple sleep.

Two more of John's tentacles shift up his body to press firmly down on his shoulders, aborting his attempt to sit up, while a third joins the first at his crotch. Curving unapologetically around his balls, it begins sliding wetly along his arse crack, making its intentions quite clear.

A whine escapes his lips as he feels himself thicken from the warmth and moistness, and the knowledge that, on some level, this is John touching him and had his friend been awake, there would be no question of consent. As it is, Sherlock can only hope that John will understand that surrendering to the tentacles aggressive seduction is a matter of when, not if.

Sherlock stops struggling to rise and the appendages seem to recognise that the fight is over, gentling their touch if not their enthusiasm. For the first time one of John's tentacles advance more in question than demand and as it taps on Sherlock's mouth it seems to carry an offer rather than obligation. Sliding his lips slightly apart the tentacle strokes gently at his lips, with a gasp of surprise, Sherlock finds the secretions sweet and slightly tangy as he laps experimentally at the liquid.

Whatever comprises the lubricating ooze, Sherlock suspects it carries an aphrodisiac quality as the sensation of heightened touch rushes through him. His balls tighten suddenly and if not for a firm grasp at the base of his cock, his orgasm would have burst upon him with reckless haste. As it is, the tentacles still for a handful of heartbeats as Sherlock gasps for breath and control, pinpricks of light dancing before his eyes.

As the strokes and thrusting resume, he gives himself over to the demands being made of him and sucks at the flesh thrust obscenely in his mouth with renewed enthusiasm as his own tentacles lie twitching and forgotten in a pile around him.

@@@

John wakes to a wet feeling of something pressing against his lips, insistently pressing until his teeth are forced apart and the slippery tentacle slips inside to wind around his tongue. Alarmed, he looks down to find the invading appendage is his own and his others are similarly invading his other orifices. The the feeling on his cock that, in his dream had been Sherlock's, is instead his own writhing pink appendage and a third is actively working its way into his arse. He opens his mouth to cry out, only to find the tentacle pushing in further and the sound is stillborn before it emerges.

John manages to turn his head to the side, pushing against the constraining flesh to seek Sherlock's help and is horrified to see that Sherlock has been similarly assaulted by his errant limbs. Not that Sherlock seems to be suffering any ill effects. Sherlock's back is arched in pleasure as the tentacle wrapped around his cock strokes confidently, and Sherlock moans around the oozing tentacle in his mouth. In fact, now that John looks more closely, Sherlock seems to be sucking avidly on the intruding limb. As John watches, Sherlock's eyelids raise slowly and his pale eyes meet John's in a look equal measures vulnerability and abandonment.

Sherlock's hand reaches out and grabs toward John as another moan is wrenched from him and John notices for the first time that like his own arse, Sherlock's is being invaded in steady, rhythmic pulses. John grasps Sherlock's outstretched hand and feels the trembling twitches in the fingers even as he is overwhelmed by the assault on his own body. He whimpers at the feedback loop of sensation caused by his tentacles on his body and the feelings transmitted through those self-same appendages.

To salvage his sanity, John clutches at his words to Sherlock a couple of days ago, " _Well it looks like this is happening regardless of our views on the matter."_ Even in the midst of pleasure, Sherlock can still read John's face like a book and nods before his eyes close and his head tilts back again as the pace of the strokes at his cock increase.

Taking the hint, John surrenders to the tentacles. Whatever their plan for them both, struggling is only likely to cause pain to either one or both of them and if John is honest with himself, if what's Sherlock's tentacles did to him last time was pleasure...this is bliss. He can feel his tentacles on Sherlock..in sherlock, as well as on himself. It's almost too much to bear.

The tentacles retract from his mouth with an obscene slurp and he notices the ones in Sherlock's have done the same. They grab hurried snatches of breath before the have the chance to gasp with rough voices.

"You OK?" John's question is simple.

"Yeah...you?" Sherlock's response is laboured but clear.

The exchange suddenly strikes John as hysterical, trapped as they are by a pile of horny tentacles and he laughs, quick and high, "As right as I can be with my own tentacle up my arse."

"Look at it this way..." Sherlock pauses as his eyes roll back in his head for a moment before they focus on John again, "You get yourself off with your hand....this is....like that."

John laughs again as something moves inside him and he shudders as it rubs against his prostate, "It's really not."

"Worth a shot...." Sherlock mumbles before he arches again.

Suddenly, Sherlock's tentacles seemingly come to life, wriggling under him and lifting him off the carpet, shifting him toward John.

"Fuck, Sherlock..what now?"

"No idea...wait..oh." Between the two sets, a compromise seems to have been reached and the two men are being drawn together and wrapped in the combines limbs. John's are still probing and stroking, but they are now joined by Sherlock's adding additional lubrication and stimulation at nipples and balls. The two men grab hungrily at each other as the pleasure builds for them both, bringing their mouths together messily.

John's hands sink amongst Sherlock's curls and for the first time, the moan is from John's touch instead of the tentacles. Sherlock hand's move to John's arse, forcing their cocks closer, the slimy ooze between them making the slide against one another easy and swift.

"Christ...Sherlock..."

"I know...." Sherlock lowers his head to John's shoulder and sucks hard, the sweaty skin drawing into his mouth and John cries out and the overt sensation of being marked. He goes rigid under Sherlock's hands and thrusts hard, shuddering with the force of his orgasm.

"Yes...Oh God, John...Yes!" Sherlock bellows the words as John's tentacle pulses and clenches inside him, ruthlessly massaging his prostate and tearing the orgasm from him before he collapses against John, whimpering as he feels the appendage slide from inside him.

They lay, panting for breath, the slippery tentacles rubbing soothing patterns on both their backs as they bonelessly slide apart.

"Jesus...Sherlock....That was..." John's shaking his head in disbelief.

"Amazing." Sherlock manages, his voice hoarse and cracked.

"And the tentacles are still here."

"I don't know....." Sherlock mutters, his words beginning to slur with exhaustion, "Worry about it in the morning."


End file.
